Results showed that using the NIST/JET ceiling jet algorithm gave a closer prediction of the sprinkler response time in a small room than Alpert's correlation. This was expected, since the former includes the effect of a hot upper layer while the latter applies to unconfined ceilings. The experiments available for comparison had been conducted inside an enclosure with a developing hot upper layer. The findings also signified that changing the sprinkler operational parameters can change the predicted sprinkler activation time significantly.

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SUMMARYResearch is ongoing to increase the functionality of the fire zone modeling software BRANZFIRE, by converting it from a deterministic to a probabilistic model. One component of this work is the development of a radiative fire spread submodel for which a suitable ignition criterion method is needed. This paper provides details of that ignition criterion procedure and its implementation into the submodel.A list of requirements that the ignition methodology had to satisfy was established. Of the many different piloted ignition models available, the Flux-Time Product technique, and its associated ignition criterion, was selected to be incorporated into the fire spread submodel. This method provides a practical engineering approximation of when a secondary fuel item that is subjected to incident radiation will ignite that is commensurate with the accuracy of the overall model.Primarily to demonstrate the use of the technique in the submodel, a series of ignition experiments were conducted on a single example of upholstered furniture using the Cone Calorimeter apparatus, with specimens tested in both the horizontal and vertical orientation, under piloted and auto ignition conditions. The experimental incident radiation and time-to-ignition data, for the piloted ignition mode, was analyzed using a modified Flux-Time Product correlation procedure.To deal with the auto ignition mode, an empirical approximation, based on the modified Flux-Time Product procedure, is proposed. Data for use in the submodel was therefore also derived for the auto ignition mode, based on an experimental determination of the minimum ignition flux.

In South Africa alone, there are more than 5000 informal settlement fires a year, where a single incident can leave up to 10000 people homeless. The government and local authorities of countries with informal settlements, that extend over large areas, have no tools to simulate fires to identify high risk areas, or to quantify the magnitude of an incident to which they may need to respond. It is with this backdrop that the paper seeks to develop a semi-probabilistic method to determine fire spread rates in informal settlements. Data from a full-scale fire experiment is used to validate the fire spread rates predicted by B-RISK from which a simplified semi-probabilistic analysis method is developed that can estimate fire spread rates in informal settlements. B-RISK simulations are then compared to an actual informal settlement fire incident to assess its predictive capabilities. The paper also discusses how the effect of wind has been included and what additional features could be incorporated to obtain more realistic informal settlement fire spread predictions. This work provides the first step in a complex problem where it is difficult to accurately define input parameters.

This paper describes validation of a cumulative radiant energy method for predicting the time to failure of non load-bearing drywall construction exposed to realistic parametric fires. The validation uses full-scale compartment fire tests and analytical calculations. Three compartment fire tests are carried out in a room 3.6 m by 2.4 m with different arrangements of fuel load and ventilation, with walls and ceilings constructed from assemblies which have been previously tested in standard fire resistance tests. The analytical calculations use a finite difference heat transfer model developed for predicting the fire performance of cavity construction, in combination with a number of Eurocode parametric fires. We conclude that the cumulative radiant energy method can be used as a valid tool for prediction of insulation failure times of drywall assemblies, during the period of fire exposure where heat transfer is predominantly by radiation. This includes the growth period to flashover, the period of sustained ventilation-controlled burning, and the early part of the decay period.

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sensitivity analysis found that fracture strength was the most important input variable, though this is largely attributable to the large standard deviation of the probability distribution used for this input.

There is a risk of a building suffering unsustainable structural damage in the event of a large fire. Therefore, it is necessary to design buildings to withstand expected fires.A widely used simplified calculation method is the so-called 'time-equivalence' method. There are significant concerns about the suitability of this method. This paper is Part I of a twofold study examining the state of the art of time-equivalence methods. The purpose of this paper is to provide a detailed background of the development of time-equivalence methods since its first introduction in 1928 and to provide an initial high-level assessment of the accuracy of these methods. A simple scoring system is used to assess the methods based on the accuracy of the analysis techniques used in their derivation. The study revealed that most methods do not account well for structural system response to fire exposure. While some timeequivalence methods do yield accurate results, further analysis is required to fully assess their suitability.